Hit points of a building can be restored by ordering Citizens to repair it. Additionally, cities will automatically heal when they have not recently taken damage: Small Cities heal at a rate of 3.75 HP per second (1 HP every 4 frames), Large Cities heal at a rate of 7.5 HP per second (2 HP every 4 frames), and Major Cities heal at a rate of 11.25 HP per second (3 HP every 4 frames).
Healing while garrisoned Edit
If a unit is garrisoned inside a building, it will automatically restore lost hit points at a low rate. A unit can always be garrisoned inside the building that created it, i.e., a catapult may garrison inside a Siege Factory while naval units may garrison inside a Dock. Infantry, cavalry and support units can also garrison inside Cities, Towers and Forts. Although some military units can garrison in other unit-producing military buildings (such as putting foot units in a Siege Factory or a Catapult in a Barracks), they will not receive healing when doing so, though they will receive healing when in their own unit-producing military building as well as in Cities, Towers, and Forts. Note that units can also garrison inside allied buildings. The unit receives healing based on the unit's nation's healing technology, not the nation of the building it's garrisoned in, when in an allied building.
If a unit can otherwise normally heal itself (such as Citizens naturally healing in friendly territory), that healing does not apply while it is garrisoned. Instead, only the garrison heal rate (if applicable) is applied.
The base healing rate for garrisoned units is 0.75 hit points per second (1 hit point per 1.33 seconds, or 1 hit point every 20 frames), which is very slow. However, it can be increased by researching various various technologies at a Granary:
|Healthcare technology||Land units||Naval units||Aircraft|
|-||0.75 HP per second|
(1 every 20 frames)
|1.07 HP per second|
(1 every 14 frames)
|0.75 HP per second|
(1 every 20 frames)
|Herbal Lore||1.0 HP per second|
(1 every 15 frames)
|1.5 HP per second|
(1 every 10 frames)
|0.94 HP per second|
(1 every 16 frames)
|Medicine||1.5 HP per second|
(1 every 10 frames)
|2.14 HP per second|
(1 every 7 frames)
|1.25 HP per second|
(1 every 12 frames)
|Pharmaceuticals||3.0 HP per second|
(1 every 5 frames)
|3.75 HP per second|
(1 every 4 frames)
|1.88 HP per second|
(1 every 8 frames)
Building the Red Fort wonder increases the healing rate of units garrisoned inside the Red Fort by 500%. Although the description says it also affects units garrisoned in other Forts, this apparently does not function. The Red Fort healing rate for units garrisoned within is:
|Healthcare technology||Red Fort healing rate|
|-||5 HP per second|
(1 every 3 frames)
|Herbal Lore||7.5 HP per second|
(1 every 2 frames)
|Medicine||15 HP per second|
(1 every frame)
|Pharmaceuticals||15 HP per second|
(1 every frame)
Allied units garrisoned inside the Red Fort heal at this rate, although the healing technology tier depends on the unit's own nation rather than the nation of the Red Fort.
Supply Wagons Edit
The French Supply Wagon heals nearby units at a fixed rate of 0.75 hit points per second (1 every 20 frames). The Versailles wonder adds this effect to the Supply Wagons of other nations as well, while doubling the rate of French Supply Wagons (to 1 every 10 frames). The healing from multiple Supply Wagons do not stack; only one is applied to a given unit. Units of allied nations cannot be healed this way, as Supply Wagons in general only have an effect on units of their own nation.
The only way to heal a Supply Wagon is by garrisoning it. Supply Wagons will not heal from healing sources, except by garrisoning. This is true even if they have the Versailles healing effect and if there is a healing Patriot nearby.
- The Senator (Republic) heals units and buildings that are in friendly territory.
- The President (Democracy) heals units and buildings that are in friendly or neutral territory.
- The CEO (Capitalism) heals units and buildings that are in any territory, as long as they are not taking attrition damage.
The healing rate is the standard 0.75 hit points per second (1 every 20 frames). The healing rate of consensus type patriots will stack additively with the healing rate of French and/or Versailles Supply Wagons.
Additionally, if the nation is French and/or has the Versailles wonder, the Supply Wagon effect of totalitarian Patriots will also heal units in their radius at the same rate above. However, this does not stack with the effect from Supply Wagons; only one is applied to a given unit.
The CEO's healing while in enemy territory is bugged. It is decreased if the attrition amount that the unit would otherwise receive (without a Supply Wagon present) is low. Thus, the Smelter anti-attrition technologies actually decrease the CEO's healing while in enemy territory. If the attrition amount (as displayed in the unit's infobox) is 20 or higher, the CEO heals at the standard rate of 0.75 hit points per second (1 every 20 frames). If the displayed attrition amount is 8, then it heals at around 87.5% of the standard rate. If the displayed attrition amount is between 4 and 6, then it heals at around 75%. A displayed attrition amount of 2 (corresponding to the first tier of attrition, with no Smelter upgrades) would mean that the CEO heals at around 50% of the standard rate. The rate decreases further at lower attrition amounts, with an attrition value of 1 (first tier of attrition with Smelter technology tier 2, or second tier of attrition with Smelter technology tier 3, etc.) giving a 33% healing rate, going down to the equivalent of an attrition amount of 1/4 (displayed as 1) having a healing rate of around 8.3% of standard. An example of this latter case would be Mongols with full Smelter technologies in enemy territory with the first tier of attrition. However, if the enemy does not have any attrition researched, then the CEO heals at the full standard rate of 0.75 hit points per second (1 every 20 frames), regardless of his Smelter research. It also functions normally (giving the standard rate) in friendly and neutral territory.
Iroquois land units within their nation's or allies' borders heal, when not moving or attacking. The rate is the same as the garrison rate above for land units (although values different from the garrison rate can be set in rules.xml for the Iroquois). Although they will start healing once they stop moving, they will not heal until 33 seconds (500 frames) have passed from when they last attacked. Thus, although garrisoning Iroquois units to heal is generally not necessary, since they heal at the same rate within friendly territory, you may still wish to do so if the units had recently attacked. Note that they can be affected by other sources of healing (such as a consensus Patriot or a Supply Wagon with the Versailles wonder) in addition to their natural healing when not garrisoned.
Civilian units Edit
Citizens, Scholars, Merchants, Armed Merchants, Caravans, and Armed Caravans automatically heal over time at a set rate of 1 hit point per 3.0 seconds (1 every 45 frames) when in friendly territory, unless they are garrisoned. Note that if converted into a Militia, the Citizen loses this healing.
Citrus (rare resource) Edit
Sending a Merchant to gather a Citrus rare resource allows naval units of that nation to heal while at sea. The healing rate is the default 1 hit point per 1.33 seconds (1 every 20 frames). It does not apply to garrisoned naval units.
Note that this is the only way to heal naval units when they are not garrisoned (except for aircraft carriers).
Aircraft Carriers Edit
Aircraft carriers will automatically heal at the rate of 1 hit point per 1.33 seconds (1 every 20 frames). This stacks with the Citrus healing. However, they cannot garrison inside a Dock or any other building to increase their healing rate.
Healing from different types of sources will stack additively with each other. This means that when there are multiple types of sources, each will contribute to a unit's healing. An exception is garrisoning a unit, in which case the unit will only receive the garrison healing rate, and only within Cities, Towers, and Forts, or within the unit's own unit-producing military building.
The fastest healing rate achievable is by garrisoning a unit inside the Red Fort. For non-garrisoning, the maximum healing rate is achieved via an Iroquois Citizen in friendly territory with all the Granary healing technologies researched and within range of a Supply Wagon with the Versailles wonder and a consensus Patriot. The unit would receive 4 different types of healing, with a total healing rate of 4.83 hit points per second (3 from Iroquois with Granary healing technologies, 0.33 from citizen, 0.75 from Supply Wagon with Versailles wonder, and 0.75 from consensus Patriot). This healing is about the same as the damage rate of a Javelineers unit firing on the Citizen. However, in general, the healing rate is low such that it shouldn't be relied on to keep a unit alive in battle. Instead, it is helpful for restoring units to full hit points while moving between battles, or (when garrisoned) to protect and restore units outside of battle.
Summary table Edit
A table of the different sources of healing and their rates is below.
|Healing Source||Healing Rate||Healing Interval|
|Garrison with no healing technologies (land unit)||0.75 HP per sec||1 every 20 frames|
|Garrison with Herbal Lore (land unit)||1.00 HP per sec||1 every 15 frames|
|Garrison with Medicine (land unit)||1.50 HP per sec||every 10 frames|
|Garrison with Pharmaceuticals (land unit)||3.00 HP per sec||1 every 5 frames|
|Garrison with no healing technologies (naval unit)||1.07 HP per sec||1 every 14 frames|
|Garrison with Herbal Lore (naval unit)||1.5 HP per sec||1 every 10 frames|
|Garrison with Medicine (naval unit)||2.14 HP per sec||1 every 7 frames|
|Garrison with Pharmaceuticals (naval unit)||3.75 HP per sec||1 every 4 frames|
|Garrison with no healing technologies (air unit)||0.75 HP per sec||1 every 20 frames|
|Garrison with Herbal Lore (air unit)||0.94 HP per sec||1 every 16 frames|
|Garrison with Medicine (air unit)||1.25 HP per sec||1 every 12 frames|
|Garrison with Pharmaceuticals (air unit)||1.88 HP per sec||1 every 8 frames|
|Red Fort garrison with no healing technologies||5.00 HP per sec||1 every 3 frames|
|Red Fort garrison with Herbal Lore||7.50 HP per sec||1 every 2 frames|
|Red Fort garrison with Medicine||15.0 HP per sec||1 every 1 frame|
|Red Fort garrison with Pharmaceuticals||15.0 HP per sec||1 every 1 frame|
|Aircraft carrier||0.75 HP per sec||1 every 20 frames|
|French Supply Wagon or Supply Wagon with Versailles||0.75 HP per sec||1 every 20 frames|
|French Supply Wagon with Versailles||1.50 HP per sec||1 every 10 frames|
|French totalitarian Patriot or totalitarian Patriot with Versailles||0.75 HP per sec||1 every 20 frames|
|French totalitarian Patriot with Versailles||1.50 HP per sec||1 every 10 frames|
|The Senator (Republic), friendly territory||0.75 HP per sec||1 every 20 frames|
|The President (Democracy), friendly or neutral territory||0.75 HP per sec||1 every 20 frames|
|The CEO (Capitalism), friendly or neutral territory||0.75 HP per sec||1 every 20 frames|
|The CEO (Capitalism), enemy territory||0.75 HP per sec or lower||1 every 20 frames or more|
|Iroquois land unit with no healing technologies, friendly territory||0.75 HP per sec||1 every 20 frames|
|Iroquois land unit with Herbal Lore, friendly territory||1.00 HP per sec||1 every 15 frames|
|Iroquois land unit with Medicine, friendly territory||1.50 HP per sec||1 every 10 frames|
|Iroquois land unit with Pharmaceuticals, friendly territory||3.00 HP per sec||1 every 5 frames|
|Citizens, Scholars, Merchants, Armed Merchants, Caravans, and Armed Caravans, friendly territory||0.33 HP per sec||1 every 45 frames|
|Ships, with Merchant deployed at Citrus rare resource||0.75 HP per sec||1 every 20 frames|